Sectional gear-wheel.



No. 786,274. PATBNTED' APR. 4, 1905.

J. T. DUFF. SEGTIONAL GEAR WHEEL.

APPLIOATION FILED AUG. 25, 1904.

Jay 2 wnnzsses NITED STATES Patented April 4, 1905.

PATENT OFFICE.

JOHN T. DUFF, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR OF TlVO- THIRDS TOWILLIAM H. LATSHAl/V, OF PITTSBURG, PENNSYLVANIA, AND JOSHUA RHODES, OFALLEGHENY, PENNSYLVANIA.

SECTIONAL GEAR-WHEEL.

SPECIFICATION forming part of Letters Patent No. 786,274, dated April 4,1905.

Application filed August 25, 1904:. Serial No. 222,168.

To [bi/Z whom it may concern:

Be it known that I, JOHN T. DUFF, a resident of Pittsburg, in the countyof Allegheny and State of Pennsylvania, have invented a new and usefulImprovement in Sectional Gear-Wheels; and I do hereby declare thefollowing to be a full, clear, and exact description thereof.

My invention relates to gear-wheels; and the object is to provide agear-wheel which is very strong, light, and durable, and especially sucha gear-wheel when so constructed that it can be put in place on andremoved from a shaft or axle without disturbing the latter or itshangers.

To these ends the invention consists, generally stated, in a gear-wheelconstructed as hereinafter described and claimed.

In the accompanying drawings, Figure 1 shows a gear-wheel, partly inside view and partly in section. Fig. 2 is a side view of one of thetooth-sections detached from the wheel; and Fig. 3 is a vertical sectionon line 3 3, Fig. 1.

My gear-wheel will comprise a body adapted for attachment to a shaft oraXle and which will have a hub and rim connected either by spokes or bya web. This body may be cast or may be formed of wrought metal, such aswrought-steel. When the latter, it preferably will be of the spokevariety and is so shown in the drawings. The drawings also show the gearof the sectional type, although certain features thereof, such as therenewable rim, can be applied to nonsectional gears.

As shown in the drawings, the body is composed of two similar sections,each comprising a hub-section 5 and a rim-section 6, united by spokes 7.Both these hub and rim sections are preferably formed of wroughtsteeland may be made by rolling. The rim-section 6 may be an ordinary rolledrectangular bar cut to length and bent to semiannular shape. Thehub-section 5 may be formed in the same way or it may be made by rollinga bar in concave form, having a cross-section similar to the section ofthe hub shown in Fig. 1, and then cutting short pieces off said bar toform said hub-sections. The spokes 7 are attached to the hub and rim,preferably by providing said spokes with tenons 8, which project throughopenings 9 in both the hub and rim sections, the outer ends of saidtenons being upset in countersunk portions 10 of said holes. In this waythe hub and rim sections are securely and firmly united. One of thehub-sections will be provided with a keyway 11 for attachment to theshaft or aXle, although this is not essential. The two body-sections aresimilar and are united by suitable dovetailed keys or gibs 13, fittingin matching undercut slots formed in the meeting edges of the hub andrim sections. Four such keys are used, two for uniting the hub-sectionsand two for uniting the rim-sections. In this manner the gear-body isfirmly secured together and forms, in effect, a rigid whole. The keys 13can be easily driven out and said body-sections separated to permit theremoval of the gear from the shaft 01' axle.

The toothed portion of my gear-wheel is formed as a separate andremovable portion, and this will be the case even though the body is notconstructed in the specific manner described or even if the gear is notmade of wrought metal. This toothed rim will be either in a singlepiece, especially when the gear is not made in separable sections; butpreferably it will be made in several sections, even though thewheel-body itself be not made in sections. The purpose of having aseparate toothed rim is to permit its renewal in case of injury, and itis preferable to have said toothed rim sectioned, so that if a tooth inone section breaks off only that portion of the rim need be renewed. Inthe drawings this toothed rim is shown formed of two similar and equalsections 15, although in actual practice the number of said sections maybe materially more than two. These rim-sections will be provided ontheir outer faces with the desired form of teeth, and they are securedto the body by means of dovetailed gibs or keys 16, driven of thebody-rim. Any necessary number of such gibs or keys can be employed, thedrawings showing four. These gibs or keys will be located in anysuitable position with referonce to the point of attachment of thespokes. These gibs are made to fit tightly, so as to hold the toothedsections firmly in place on the wheel-body. They nevertheless can bedriven out whenever it is necessary to renew any portion of the toothedrim. To prevent the keys from jarring loose, they are each provided witha depression 17 for receiving the end of a binding-screw 18, fitting ina tapped hole in the body-rim. If desired, the keys may be integral witheither the toothed rim or the body portion. This plan can be followed,especially when the body is made by casting.

The rim portion 6 of the wheel-body has its outer or peripheral facesubstantially parallel to the axis of the wheel, and the toothedrim-sections 15 have corresponding inner faces. The keyways are formedin these parallel faces, and the dovetailedkeys draw the rim-sectionsdown tightly against the outer face of the body rim portion.Consequently the removable toothed rim-sections are held firmly in placeand are backed for their entire lengths and widths by the solid metal ofthe body rim portion and can therefore efficiently resist all strainsand thrusts.

Preferably the toothed rim-sections will be formed of forged steel andwill be tempered and hardened after being bent to shape and having theteeth out thereon. They will thus be able to withstand severe wear, andthe life of the gear-teeth will be many times greater than ingear-wheels now in use. Should any of the teeth break off or becomeunduly worn, that particular section of the toothed rim can be readilyreplaced by a new one, so that the entire wheel need not be discarded,as is now the case.

The gear-wheel described can be made very light in proportion to thestrength thereof. The wearing qualities thereof are many times greaterthan of any gear-wheel in use at the present time. N 0 part thereof issubject to wear except the teeth, and these can be renewed whenevernecessary. As a conse quence the wheel will be very economical whencompared with existing forms of gearwheels.

I wish it understood that all features of my invention need notnecessarily be embodied in a single gear-wheel. For instance, the renewable toothed rim may be used in conjunction with a body materiallydifferent from that shown and described and may even be used on a bodywhich is not separable. Various changes also may be made in the detailsof construction without departing from the spirit of my invention.

What I claim is 1. A gear-wheel comprising a body adapted to be securedto a shaft and having a peripheral face substantially parallel to itsaxis, a removable and renewable toothed rim provided with an inner facecorresponding to the peripheral face of the body, and keys driven intomatching slotsin said body and rim-faces and serving to secure the sametogether.

2. A gear-wheel comprising a body adapted to be secured to a shaft andhaving a peripheral face substantially parallel to its axis, a toothedrim formed in several sections each provided with an inner facecorresponding to the peripheral face of the body, and dovetailed keysfitting in matching undercut slots in the meeting faces of the body andrim sections and serving to secure the same together.

3. A gear-wheel comprising a body composed of several sections, meansfor securing said body-sections together, a sectional toothed rim, anddovetailed keys fitting in matching undercut slots in the body andtoothed rim-sections and serving to secure them together.

4:. A gear-wheel comprising a body composed of several sections eachhaving a peripheral face substantially parallel to the axis of thewheel, means for securing said body sections together, a toothed rimformed in several sections each provided with an inner facecorresponding to the peripheral face of the body, and dovetailed keysfitting in matching undercut slots in the meeting faces of the body andrim sections and serving to secure the same together.

5. A gear-wheel comprising a body composed of two sections, dovetailedkeys fitting in matching undercut slots in said bodysections and servingto secure the same together, a toothed rim formed in several sections,and dovetailed keys fitting in matching undercut slots in said body andrim sections and serving to secure the same together.

6. A gear-wheel comprising a sectional body, each section composed of ahub and rim portions and spokes uniting the same, means for uniting saidbody-sections, a sectional toothed rim, and dovetailed keys fitting inmatching undercut slots in said body and rim sections and serving tosecure the same together.

7. A gear-wheel comprising a sectional body, each section formed of ahub and rim portions and spokes uniting the same and all formed ofwrought metal, means for securing said body-sections together, asectional toothed rim formed of hardened steel, and dovetailed keysfitting in undercut matching slots in the body and rim sections andserving to secure the same together.

8. A wrought-metal gear-wheel comprising a hub, a rim, and spokes upsetin said hub and rim, said gear-wheel being formed in two separablesections, and dovetailed keys fitting in undercut matching slots in thehub and rim portions of the two sections and serving to secure the sametogether.

9. A gear-wheel comprising a body adapted to be secured to a shaft andhaving a peripheral face substantially parallel to its axis, a removableand renewable toothed rim formed in several sections each provided withan inner face corresponding to the peripheral face of the body, andmeans for securing said rim to said body.

10. A gear-wheel comprising a body adapted to be secured to a shaft andhaving a peripheral face substantially parallel to its axis, a removableand renewable toothed rim formed in several sections and each composedof hardened steel and provided with an inner face corresponding to theperipheral face of the body, and means for securing said rim to saidbody.

In testimony whereof I, the said JOHN T. DUFF, have hereunto set myhand.

JOHN T. DUFF.

Witnesses:

F. WV. WINTER, ROBERT C. ToTTEN.

